It has been known to form extremely contrasty photographic images by combining a hydrazine derivative and certain kinds of silver halide emulsions, and such image-forming processes have been employed in the photoengraving field.
For example, it has been known to obtain superhigh contrast negative images by processing a surface latent image-forming silver halide photographic material containing a hydrazine derivative (for example, a specific acylhydrazine compound as described in U.S. Pat. Nos. 4,166,742, 4,168,977, 4,211,857, 4,224,401, 4,243,739, 4,272,606 and 4,311,781) with a solution having a pH of 11.0 to 12.3 and containing a sulfite preservative in a concentration of 0.15 mol/liter or more.
This process enables one to obtain a superhigh contrast tone (as high as more than 10 in gamma value). However, since it utilizes an infectious development mechanism due to the hydrazine derivatives, the characteristics of the silver halide emulsion grains are also amplified as a result of the development.
In particular, it is well known that not only light-sensitive materials containing hydrazine derivatives but also other light-sensitive materials generally undergo generation of photoelectrons or lattice defects when pressure is applied to silver halide emulsion grains upon the materials being bent or scratched, and that they suffer sensitization, desensitization or fogging in the pressure-applied areas. Thus, various techniques have been employed for improving pressure resistance.
For example, it has been known to prevent pressure from reaching the particles by incorporating a plasticizer such as a polymer or an emulsion, or by decreasing the ratio of silver halide/gelatin in the silver halide emulsion.
As illustrative, British Pat. No. 738,618 discloses using heterocyclic compounds, British Pat. No. 738,637 discloses using alkyl phthalates, British Pat. No. 738,639 discloses using alkyl esters, U.S. Pat. No. 2,960,404 discloses using polyhydric alcohols, U.S. Pat. No. 3,121,060 discloses using carboxyalkyl cellulose, JP-A-49-5017 (the term "JP-A" as used herein refers to a "published unexamined Japanese patent application") discloses using a paraffin and a carboxylate, and JP-B-53-28086 (the term "JP-B" as used herein refers to an "examined Japanese patent publication") discloses using an alkyl acrylate and an organic acid.
As a technique for improving pressure properties of superhigh contrast light-sensitive materials containing a hydrazine derivative, JP-A-62-21143 discloses adding polyhydroxy-substituted benzenes. However, this technique is not fully satisfactory comparing its advantages with disadvantages (deterioration of adhesion resistance).
On the other hand, a novel image-forming system using a hydrazine derivative has the defect that, where the number of processed films is small, black peppers are seriously formed when the concentration of sulfite incorporated in the developer as a preservative is reduced due to fatigue of the developer with time or when the pH is increased. As technique for solving this problem, there is a technique of increasing the amount of a replenishing developer. However, this technique involves a problem of an increase in developer cost and a problem with waste liquor. Thus, it has been desired to develop a system or a film which does not suffer the formation of black peppers even when the amount of replenishing developer is not increased.